https://www.smithsonianmag.com/travel/the-worlds-largest-mammal-migration-is-taking-pla...

"Straw-colored fruit bats (Eidolon helvum) arrive at Kasanka, in Zambia’s Central Province, from various corners of the country and continent. They settle into the cool, swampy forest waiting for nightfall so they can arise en masse and turn the surrounding farmlands and woods into an all-you-can-eat fruit buffet. At dawn, the nocturnal mammals return to the forest to sleep off their meals,

"Witnessing the bats in flight is a mind-blowing display of nature that truly has to be seen to be believed.

"This is the Largest Mammal Migration in the World.

"The so-called megabats, which look like flying foxes, fly in from the Democratic Republic of Congo, parts of Zambia, and sometimes Tanzania and Malawi, coming each year to fill the woods with their chirps and hang off the trees like icicles. They typically start drifting into the park around October and leave in January, though local guides say this year the first bats came on September 26, perhaps due to the country’s ongoing drought or the ripple effects of climate change.

***

"The straw-colored fruit bat is the only long-distance migrating fruit bat on the continent, and it’s believed that bats from several different colonies meet at Kasanka. As for why the bats come to Kasanka specifically every year, it’s a bit of a mystery. Scientists know that these straw-colored fruit bats aren’t congregating in Kasanka to breed, as they likely breed in Mozambique and Tanzania.

“'In terms of understanding the reasons for migration—the tendencies for migration for bats—we don’t have a whole lot of background in it, but we believe they come for the food,” says Teague O’Mara, an expert on bat movement and behavior and the director of conservation evidence at Bat Conservation International.

***

"But if they’re here for the buffet, O’Mara isn’t sure why the bats come to Kasanka specifically from October to January, because the fruit is ripe and available for eating at other times of the year, too.

"Straw-colored fruit bats play a vital role in the ecosystem. “They’re the best seed dispersers,” says O’Mara. “They really are Africa’s gardeners.” Since the bats love fruit, they eat as much as they can, digest the seeds and then leave them in their wake as they fly. “They’re depositing seeds in places that no other seed disperser will go. They have the potential to restore a lot of economically important timber species,” he adds. And yet several factors are contributing to a decline in their population, which numbers somewhere in the millions. Their habitat is being threatened by deforestation, with humans cutting down their roosts for farms and houses. Zambia reportedly has one of the highest rates of deforestation around the globe, which harms the bat population. People have also been known to eat the bats. They are currently listed as a near threatened species by the International Union for Conservation of Nature.

"The loss of straw-colored fruit bats would have both ecological and financial implications. That’s because a colony of 100,000 or so bats can have a real-world financial impact. That one colony “can put about $800,000 worth of economic value into the economy every year,” says O’Mara. “And that’s just by doing what they naturally do.”

***

"One of the reasons that scientists haven’t been able to track the migratory patterns of the bats closely is due to a basic tech problem. “We don’t have GPS tags or other tags that can last an entire year,” O’Mara says.

"Another mystery is why the bats don’t live in Kasanka year-round. “We see, particularly in places where there’s less seasonality across Equatorial Africa and Accra [Ghana], that there are populations that have big influxes of migratory animals, but they’ll have a stable population throughout the rest of the year,” says O’Mara. “That doesn’t happen in Kasanka. Once January hits, all the bats are gone.”

"Scientists, however, are slightly more confident about where bats go when they leave the national park. “We’ve seen them going into Congo. We’ve seen them going out into Malawi and start heading north into Tanzania. And then we’ve tracked one that has gone through Congo and up into South Sudan,” says O’Mara. On their travels, the bats are mostly looking for fruit and for each other. “They’re highly colonial,” he says. “They love to be around each other. They always tend to roost in really big aggregations, at least as far as the ones that we can find.”

***

"They determined that around a million bats were roosting in Kasanka at peak season in November 2019. O’Mara and the guides at the park think that number is far too low. “Just use your eyes,” says Siame, who watches the bats twice a day nearly every day when they are in the park. “That is way more than a million bats.” The guides believe the true number of bats is on the higher end of what even O’Mara cited, which was a number between 10 million and 12 million bats."

Comment: this looks like a learned behavior, but if the fruit is there year round why do they leave? Perhaps it is all instinct, but the studies are too early to give us an answer.

https://www.sciencealert.com/worlds-largest-seabirds-follow-sound-across-the-ocean-to-f...

"Arctic terns travel from the Arctic to Antarctica and back as part of their annual migration. Wandering albatrosses (Diomedea exulans) fly the equivalent of ten times to the Moon and back over their lifetimes.

"There has been a lot of research into how seabirds choose their flight paths and find food. They seem to use their sight or sense of smell to assess local conditions.

"Wandering albatrosses can travel more than 10,000km in a single foraging trip, though, and we don't know much about how these birds use mid- and long-range cues from their environment to decide where to go.

"For the first time, however, my team's recent study gives an insight into how birds such as wandering albatrosses may use sound to determine what conditions are like further away.

"Previous research has shown that seabirds not only seek information about where to find food, but how to do so efficiently. We discovered that the way wandering albatrosses use their sense of sound may be crucial.

"Our study looked at how these birds respond to a very low-frequency type of sound called infrasound, which can travel for thousands of kilometres.

"While it's typically inaudible to humans, we know that some animals can hear infrasound. When waves crash together or against coastlines, they create a frequency of infrasound called microbarums. This was the type of infrasound our study looked at.

***

"Infrasound is also generated when waves crash against coastlines, and we know that many coastal seabirds use the coast to select their flight paths and find their way back to their breeding colonies. So, infrasound could reveal the location of static features like coastlines, giving seabirds important information across long distances.

"Despite the potential of this cue for seabirds, our paper (published in PNAS) is the first evidence that seabirds may respond to infrasound, which is monitored globally through a network of sensors installed by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO).

"This system was installed to detect nuclear tests, but its byproduct is huge amounts of data which scientists can use. We combined the CTBTO's records with our own GPS tracking data from 89 wandering albatrosses to compare microbarums and the birds' movements.

"This allowed us to isolate data that showed how these albatrosses appeared to make decisions about where to go next. Our findings showed they chose the direction with the loudest infrasound.

"This suggests the birds could use infrasound to find food or to minimise the energy they use on their travels. However, we are not able to say for sure why louder areas are better.

Comment: Long sea migrations must have some guidance principles. We know of using the Earth's magnetic field. Using different ranges of sound is a very interesting theory. How did this evolve is the question. Short trips becoming longer over time could teach the birds to follow sounds for food. Thus a learned instinct. The alternative is coded by design.

https://phys.org/news/2022-11-young-trees-insect-bugs.html

"Bats help keep forests growing. Without bats to hold their populations in check, insects that munch on tree seedlings go wild, doing three to nine times more damage than when bats are on the scene. That's according to a new study from the University of Illinois. The article, "Bats reduce insect density and defoliation in temperate forests: an exclusion experiment," is published in Ecology.

***

"The research team built giant mesh-enclosed structures in an Indiana forest to exclude the eight bat species that frequent the area, including two federally threatened or endangered species. The mesh openings were large enough to allow insects free movement in and out, but not flying bats. Every morning and evening for three summers, Beilke opened and closed the mesh sides and tops of the structures to ensure birds had daytime access to the plots. That way, she could be sure she was isolating the impacts of bats.

"Beilke then measured the number of insects on oak and hickory seedlings in the forest understory, as well as the amount of defoliation per seedling. Because she erected an equal number of box frames without mesh, Beilke was able to compare insect density and defoliation with and without bats.

"Overall, the researchers found three times as many insects and five times more defoliation on the seedlings when bats were excluded than in control plots that allowed bats in each night. When analyzed separately, oaks experienced nine times more defoliation and hickories three times more without bats.

"'We know from other research that oaks and hickories are ecologically important, with acorns and hickory nuts providing food sources for wildlife and the trees acting as hosts to native insects. Bats use both oaks and hickories as roosts, and now we see they may be using them as sources of prey insects, as well. Our data suggest bats and oaks have a mutually beneficial relationship," Beilke says.

"While insect pressure was intense in plots without bat predation, the seedlings didn't succumb to their injuries. But the researchers say long-term bat declines could prove fatal for the baby trees.

"'We were observing sublethal levels of defoliation, but we know defoliation makes seedlings more vulnerable to death from other factors such as drought or fungal diseases. It would be hard to track the fate of these trees over 90 years, but I think a natural next step is to examine the impact of persistent low levels of defoliation on these seedlings," Beilke says. "To what extent does repeated defoliation reduce their competitive ability and contribute to oak declines?"

"The researchers point out that birds, many of which share the same insect diets as bats, are also declining. While they specifically sought to isolate bats' impact on forest trees, the researchers are confident insect density and defoliation rates would have been higher if they had excluded both birds and bats in their study. In fact, similar exclusion studies focusing on birds failed to account for bats in their study designs, leaving mesh enclosures up all night.

"'When we were initially working on the proposal for this research, we looked at 37 different bird exclusion studies, across agriculture and forest systems. We found nearly all of them had made this mistake. Most of them had not opened or removed their treatment plots to bats," Beilke says.

"In other words, before Beilke's study, birds were getting at least partial credit for work bats were doing in the shadows."

Comment: more important information about this ecosystem.

https://phys.org/news/2021-03-unusual-creature-winter-slumber-scientists.html

"If you binged on high-calorie snacks and then spent the winter crashed on the couch in a months-long food coma, you'd likely wake up worse for wear. Unless you happen to be a fat-tailed dwarf lemur.

"This squirrel-sized primate lives in the forests of Madagascar, where it spends up to seven months each year mostly motionless and chilling, using the minimum energy necessary to withstand the winter. While zonked, it lives off of fat stored in its tail.

***

"'Hibernation is literally in their DNA," Blanco said.

***

"For four months, the eight lemurs in the study spent some 70% of their time in metabolic slow-motion: curled up, cool to the touch, barely moving or breathing for up to 11 days at a stretch, showing little interest in food—akin to their wild counterparts.

"Now that spring is afoot in North Carolina and the temperatures are warming, the lemurs are waking up. Their first physical exams after they emerged showed them to be 22% to 35% lighter than they were at the start but otherwise healthy. Their heart rates are back up from just eight beats per minute to about 200, and their appetites have returned.

"We've been able to replicate their wild conditions well enough to get them to replicate their natural patterns," said Erin Ehmke, who directs research at the center.

"Females were the hibernation champs, out-stuporing the males and maintaining more of their winter weight. They need what's left of their fat stores for the months of pregnancy and lactation that typically follow after they wake up, Blanco said.

***

"Blanco suspects the impressive energy-saving capabilities of these lemurs may also relate to another trait they possess: longevity. The oldest dwarf lemur on record, Jonas, died at the Duke Lemur Center at the age of 29. The fact that dwarf lemurs live longer than non-hibernating species their size suggests that something intrinsic to their biological machinery may protect against aging."

Comment: These folks learned how to replicate wild conditions in their lab. We all know what hibernation looks like. Maybe they'll find out how it works. If it is their DNA as a special code, how did that happen? How did they learn to hibernate? Or did God adjust their code?

https://phys.org/news/2020-12-torpor-neat-survival-thought-rare.html

"Life is hard for small animals in the wild, but they have many solutions to the challenges of their environment. One of the most fascinating of these strategies is torpor. Not, to be confused with sleep or Sunday afternoon lethargy, torpor is a complex response to the costs of living.

"To enter torpor, an animal decreases its metabolism, reducing its energy requirements. A torpid animal will often be curled in a tight ball in its nest and look like it's sleeping.

"Once thought to occur only in birds and mammals in the Northern Hemisphere where winters are more pronounced, we now know torpor is widespread in small Australian mammals, and has also been observed in many small Australian bird species.

***

"With a lower metabolic rate, the animal's body temperature decreases—sometimes by as much as 30°C. How low it goes can depend on the extent of the metabolic reduction and the temperature of animal's immediate environment. The reduced body temperature further lowers the metabolic rate.

***

"Many pregnant and lactating bats and marsupials, and even the echidna, synchronise torpor with reproduction to cope with the energetic costs of mating, pregnancy or lactation.

There are two main types of torpor: daily torpor and hibernation.

***

"Animals that hibernate lower their metabolic rate further and have longer torpor bouts than those that use daily torpor. An example of an Australian hibernator is the eastern pygmy possum, a 40g marsupial found in south eastern Australia that hibernates regularly, decreasing its body temperature from approximately 35 °C to as low as 5°C.

"When active, this species can survive for less than half a day on 1g of fat, but when hibernating, it can survive for two weeks.

***

"The question people often ask about torpor, is "can humans do it?" Interestingly, some small primates have been observed using torpor. While it is technically possible to induce torpor in humans chemically, torpor is a very complex physiological process, and there are many aspects of it scientists still don't fully understand."

Comment: The final comment above suggests that this process would be hard to evolve naturally. It is such an integrated and convoluted physiological process involving multiple alterations in metabolism, it must have been designed by God to have this degree of convergence in evolution.

https://www.livescience.com/61018-turtles-breathe-through-butt.html?utm_source=ls-newsl...

"As an ectotherm — an animal that relies on an external source of heat — a turtle's body temperature tracks that of its environment. If the pond water is 1℃, so is the turtle's body.

"But turtles have lungs and they breathe air. So, how is it possible for them to survive in a frigid pond with a lid of ice that prevents them from coming up for air? The answer lies in the relationship between body temperature and metabolism.

"A cold turtle in cold water has a slow metabolism. The colder it gets, the slower its metabolism, which translates into lower energy and oxygen demands.

"When turtles hibernate, they rely on stored energy and uptake oxygen from the pond water by moving it across body surfaces that are flush with blood vessels. In this way, they can get enough oxygen to support their minimal needs without using their lungs. Turtles have one area that is especially well vascularized — their butts.

***

"With very few exceptions (e.g., box turtles), adult turtles cannot survive freezing temperatures; they cannot survive having ice crystals in their bodies. This is why freshwater turtles hibernate in water, where their body temperatures remain relatively stable and will not go below freezing.

Water acts as a temperature buffer; it has a high specific heat, which means it takes a lot of energy to change water temperature. Pond water temperatures remain quite stable over the winter and an ectotherm sitting in that water will have a similarly stable body temperature. Air, on the other hand, has a low specific heat so its temperature fluctuates, and gets too cold for turtle survival.

"An ice-covered pond presents two problems for turtles: they can't surface to take a breath, and little new oxygen gets into the water. On top of that, there are other critters in the pond consuming the oxygen that was produced by aquatic plants during the summer.

"Over the winter, as the oxygen is used up, the pond becomes hypoxic (low oxygen content) or anoxic (depleted of oxygen). Some turtles can handle water with low oxygen content — others cannot.

"Snapping turtles and painted turtles tolerate this stressful situation by switching their metabolism to one that doesn't require oxygen. This ability is amazing, but can be dangerous, even lethal, if it goes on for too long, because acids build up in their tissues as a result of this metabolic switch.

"An ice-covered pond presents two problems for turtles: they can't surface to take a breath, and little new oxygen gets into the water. On top of that, there are other critters in the pond consuming the oxygen that was produced by aquatic plants during the summer.

"Over the winter, as the oxygen is used up, the pond becomes hypoxic (low oxygen content) or anoxic (depleted of oxygen). Some turtles can handle water with low oxygen content — others cannot.

"Snapping turtles and painted turtles tolerate this stressful situation by switching their metabolism to one that doesn't require oxygen. This ability is amazing, but can be dangerous, even lethal, if it goes on for too long, because acids build up in their tissues as a result of this metabolic switch.

***

"My research group has monitored several species of freshwater turtles during their hibernation. We attach tiny devices to the turtles' shells that measure temperature and allow us to follow them under the ice.

"We've found that all species choose to hibernate in wetland locations that hover just above freezing, that they move around under the ice, hibernate in groups and return to the same places winter after winter."

Comment: the question is how this developed and it requires a metabolic switch in some species. One cannot simply swim to the bottom and outwait winter. It is logical to say it was all developed at once, but if that is the case it requires God to arrange it.

https://www.sciencedaily.com/releases/2017/11/171122124027.htm

"Cataglyphis fortis desert ants can learn visual or olfactory cues to pinpoint their nest, but only if these cues are unique to specify the nest entrance. Scientists from the Max Planck Institute for Chemical Ecology in Jena, Germany, discovered that the insects ignore visual landmarks or odors as nest-defining cues, if these occur not only near the nest but also along the route. Hence, ants are able to evaluate the informative value of such cues and are not fooled by ubiquitous unreliable cues.

"Homing desert ants are able to distinguish unambiguous from ambiguous landmarks and include this information in their behavioral responses when returning to their nest. This ability became obvious in behavioral experiments in Tunisia. "The ants ignored visual or olfactory cues that were not reliable. Unreliable nest cues are those that are not only found at the nest entrance, but are ubiquitous along the route. The ability to assess the informational value of visual landmarks or odor trails as relevant or irrelevant for the nest search is another example of the amazing cognitive performance of the tiny ant brain," says Roman Huber, the first author of the study.

***

"Homing desert ants are able to distinguish unambiguous from ambiguous landmarks and include this information in their behavioral responses when returning to their nest. This ability became obvious in behavioral experiments in Tunisia. "The ants ignored visual or olfactory cues that were not reliable. Unreliable nest cues are those that are not only found at the nest entrance, but are ubiquitous along the route. The ability to assess the informational value of visual landmarks or odor trails as relevant or irrelevant for the nest search is another example of the amazing cognitive performance of the tiny ant brain," says Roman Huber, the first author of the study.

***

"If one part of the landmark was unambiguous and only found near the nest, whereas the other was ubiquitous and found repeatedly along the route, the ants only used the unambiguous part, for example the odor, as reliable information and navigated towards this cue on their way back to the nest. They did not pay any attention to the several other black cards (the ambiguous part of the nest cue) they encountered in the channel," Roman Huber summarizes."

Comment: The ant brain may be tiny but it obviously has very complex neurologic networks to allow this kind of discerning ability. The point is size is only one discerning characteristic in judging the ability of a brain to function in a complex way. Highly sophisticated neural networks undoubtedly play a larger role. This is relevant in discussing brain size and function in any organisms.

DAVID: I fully understand your agnosticism. You see the need for design, but can't find a designer.

dhw: It’s not that simple. I see a conscious designer (your God), atheistic chance and atheistic panpsychism as equally unbelievable explanations. And so actual belief, as you have always acknowledged, requires faith – i.e wilfully closing one’s eyes to the great gaps in all three hypotheses. I can’t do that. Your explanation of my agnosticism is therefore too one-sided. An atheist would say: “You see the absurdity of the supernatural God hypothesis, but you can’t find a natural explanation for life.”
However, one of those hypotheses must be closer to the truth than the others, so I am horribly wrong one way or the other!

DAVID: Your phrase, 'closer to the truth' is the key to your thinking. I view one of the three as THE truth. You imply there is possibly a fourth way or more and we can never know for sure, and you cannot except anything beyond absolute proof.

dhw: “Closer to the truth” allows for variations (such as polytheism, pantheism). No, we can never know for sure unless there is an afterlife when all is revealed, and you know as well as I do that otherwise absolute proof is impossible. The best you can do is shut your eyes to the flaws in whatever hypothesis you choose, or stay on the fence. I continue to have respect for those who make a choice, so long as they don’t ridicule those who choose differently, and I expect them to have the same respect for my non-choice – which I know from our long years of friendship that you do.

I absolutely respect your non-choice. Our discussion allows all others to review their own choices.

dhw: It’s not that simple. I see a conscious designer (your God), atheistic chance and atheistic panpsychism as equally unbelievable explanations. And so actual belief, as you have always acknowledged, requires faith – i.e wilfully closing one’s eyes to the great gaps in all three hypotheses. I can’t do that. Your explanation of my agnosticism is therefore too one-sided. An atheist would say: “You see the absurdity of the supernatural God hypothesis, but you can’t find a natural explanation for life.”
However, one of those hypotheses must be closer to the truth than the others, so I am horribly wrong one way or the other!

DAVID: Your phrase, 'closer to the truth' is the key to your thinking. I view one of the three as THE truth. You imply there is possibly a fourth way or more and we can never know for sure, and you cannot except anything beyond absolute proof.

“Closer to the truth” allows for variations (such as polytheism, pantheism). No, we can never know for sure unless there is an afterlife when all is revealed, and you know as well as I do that otherwise absolute proof is impossible. The best you can do is shut your eyes to the flaws in whatever hypothesis you choose, or stay on the fence. I continue to have respect for those who make a choice, so long as they don’t ridicule those who choose differently, and I expect them to have the same respect for my non-choice – which I know from our long years of friendship that you do.

dhw: I do not "deny" the designer or chance or the panpsychist hypothesis, but I cannot believe in any of them, since all of them defy logic in one way or another. In one post you understand my agnosticism, and in another you don’t.

DAVID: I fully understand your agnosticism. You see the need for design, but can't find a designer.

dhw: It’s not that simple. I see a conscious designer (your God), atheistic chance and atheistic panpsychism as equally unbelievable explanations. And so actual belief, as you have always acknowledged, requires faith – i.e wilfully closing one’s eyes to the great gaps in all three hypotheses. I can’t do that. Your explanation of my agnosticism is therefore too one-sided. An atheist would say: “You see the absurdity of the supernatural God hypothesis, but you can’t find a natural explanation for life.”

However, one of those hypotheses must be closer to the truth than the others, so I am horribly wrong one way or the other!

Your phrase, 'closer to the truth' is the key to your thinking. I view one of the three as THE truth. You imply there is possibly a fourth way or more and we can never know for sure, and you cannot except anything beyond absolute proof.

DAVID: I fully understand your agnosticism. You see the need for design, but can't find a designer.

It’s not that simple. I see a conscious designer (your God), atheistic chance and atheistic panpsychism as equally unbelievable explanations. And so actual belief, as you have always acknowledged, requires faith – i.e wilfully closing one’s eyes to the great gaps in all three hypotheses. I can’t do that. Your explanation of my agnosticism is therefore too one-sided. An atheist would say: “You see the absurdity of the supernatural God hypothesis, but you can’t find a natural explanation for life.”

However, one of those hypotheses must be closer to the truth than the others, so I am horribly wrong one way or the other!

dhw: As for alternatives to your God, you know perfectly well that one is chance and one is the panpsychist hypothesis I have described over and over again (bottom up evolution), and you know that I find these hypotheses as difficult to believe in as the universal sourceless conscious mind you call God. And that is why I am an agnostic. (See also my response to the article on panpsychism)

DAVID: Yes I understand your hang ups.

dhw: I do not "deny" the designer or chance or the panpsychist hypothesis, but I cannot believe in any of them, since all of them defy logic in one way or another. In one post you understand my agnosticism, and in another you don’t.

I fully understand your agnosticism. You see the need for design, but can't find a designer.

DAVID: But this is Tony's magic for which you have no logical explanation. You can logically see the design as a strong argument for design and deny the need for a designer.

The design is a strong argument for a designer, and I do not "deny" it. It is a major factor in my inability to embrace atheism. Under “dangerous bacteria” we had the following exchange:

dhw: As for alternatives to your God, you know perfectly well that one is chance and one is the panpsychist hypothesis I have described over and over again (bottom up evolution), and you know that I find these hypotheses as difficult to believe in as the universal sourceless conscious mind you call God. And that is why I am an agnostic. (See also my response to the article on panpsychism)

DAVID: Yes I understand your hang ups.

I do not "deny" the designer or chance or the panpsychist hypothesis, but I cannot believe in any of them, since all of them defy logic in one way or another. In one post you understand my agnosticism, and in another you don’t.

dhw: I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

Tony: So... if I read this right, you are saying that some things evolved, some didn't. Some things just started off fully functional and functionally perfect. It's like magic!But just because we have direct evidence that some things didn't evolve, we believe that other things did evolve, because we like to limit our belief in magic, and everything popping up functionally perfect would be suspiciously magical, and we can't have that. Harumph!

dhw: No, my hypothesis entails only one form of “magic”, which offers us the best evidence of design, and that is the first living cells. They arrived fully functional and functionally perfect. And within their perfection lay a mechanism that enabled them not only to reproduce but also to combine with other cells to expand their range of functions.

But this is Tony's magic for which you have no logical explanation. You can logically see the design as a strong argument for design and deny the need for a designer.

DAVID: I see it as an explanation for things like the human brain that are too complex for the necessity of survival. Comparing it to the chimp does not address the point. The chimp lives and is happy.

Once again, I see the complexity of the human brain as the product of the drive for improvement and not just survival, though one cannot draw a strict borderline between them, since improvement can also refer to survival (the invention of spears was an improvement over trying to kill a dangerous animal with one’s bare hands). I don’t know about “happy” chimps, but ALL non-human organisms that survive manage to do so without a human brain, so you can say they live and are happy, so what point are you addressing? Mine is that the human brain evolved through the quest for improvement, whereas yours seems to be that it evolved through the quest for complexity.

dhw: I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

Tony: So... if I read this right, you are saying that some things evolved, some didn't. Some things just started off fully functional and functionally perfect. It's like magic!But just because we have direct evidence that some things didn't evolve, we believe that other things did evolve, because we like to limit our belief in magic, and everything popping up functionally perfect would be suspiciously magical, and we can't have that. Harumph!

No, my hypothesis entails only one form of “magic”, which offers us the best evidence of design, and that is the first living cells. They arrived fully functional and functionally perfect. And within their perfection lay a mechanism that enabled them not only to reproduce but also to combine with other cells to expand their range of functions. New combinations that did not start off fully functional would not have survived. Every single cellular community that survives HAS to start off fully functional, but the mechanism passed on from those first cells also enables existing cell communities (organisms) to adapt to changing environments and even to invent new structures that will enable to them to exploit new conditions. (That doesn't mean EVERY individual has to change. Single-celled organisms have survived very nicely, even if their buddies went on to bigger things.) An organism that could not get enough food on land might explore the water and find an abundance of food. The cell communities would then restructure themselves to enable the organism to live more comfortably in the water. Hence the land-dwelling pre-whale that ultimately became the whale. The “magic” is the inventive intelligence of the cell communities of which all organisms are made, and I see no reason at all why a theist should doubt the capacity of his/her God to create such a mechanism. Furthermore, it explains what some of us believe to be the facts of life’s history.

dhw: It is indeed obvious that if any particular form of life survives without changing, it doesn’t need to change! We have said the same thing over and over again about bacteria. You like to talk of a drive to complexity, and I prefer to talk of a drive for survival and/or improvement. The former is a response to stresses and challenges, and the latter is a response to opportunities. As before, I see no purpose in complexity just for the sake of complexity.

DAVID: Your response does not explain the human brain. It goes way beyond simple survival.

dhw: Of course it does. It comes under “improvement” – or do you not agree that the human brain is an improvement over the ant brain, the weaverbird brain, the chimp brain in terms of its capabilities?

DAVID: A drive for survival implies a necessity for response to challenges. The human brain is not needed for that. Your improvement then is equal to my complexity drive.

dhw: All dealt with above. I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

Tony: So... if I read this right, you are saying that some things evolved, some didn't. Some things just started off fully functional and functionally perfect. It's like magic!But just because we have direct evidence that some things didn't evolve, we believe that other things did evolve, because we like to limit our belief in magic, and everything popping up functionally perfect would be suspiciously magical, and we can't have that. Harumph!

dhw just can't have everything perfect from the beginning of its appearance. Sounds like intelligent design.

dhw: It is indeed obvious that if any particular form of life survives without changing, it doesn’t need to change! We have said the same thing over and over again about bacteria. You like to talk of a drive to complexity, and I prefer to talk of a drive for survival and/or improvement. The former is a response to stresses and challenges, and the latter is a response to opportunities. As before, I see no purpose in complexity just for the sake of complexity.

DAVID: Your response does not explain the human brain. It goes way beyond simple survival.

dhw: Of course it does. It comes under “improvement” – or do you not agree that the human brain is an improvement over the ant brain, the weaverbird brain, the chimp brain in terms of its capabilities?

DAVID: A drive for survival implies a necessity for response to challenges. The human brain is not needed for that. Your improvement then is equal to my complexity drive.

All dealt with above. I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

So... if I read this right, you are saying that some things evolved, some didn't. Some things just started off fully functional and functionally perfect. It's like magic!But just because we have direct evidence that some things didn't evolve, we believe that other things did evolve, because we like to limit our belief in magic, and everything popping up functionally perfect would be suspiciously magical, and we can't have that. Harumph!

dhw: It is indeed obvious that if any particular form of life survives without changing, it doesn’t need to change! We have said the same thing over and over again about bacteria. You like to talk of a drive to complexity, and I prefer to talk of a drive for survival and/or improvement. The former is a response to stresses and challenges, and the latter is a response to opportunities. As before, I see no purpose in complexity just for the sake of complexity.

DAVID: Your response does not explain the human brain. It goes way beyond simple survival.

dhw: Of course it does. It comes under “improvement” – or do you not agree that the human brain is an improvement over the ant brain, the weaverbird brain, the chimp brain in terms of its capabilities?

DAVID: A drive for survival implies a necessity for response to challenges. The human brain is not needed for that. Your improvement then is equal to my complexity drive.

dhw: All dealt with above. I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

I see it as an explanation for things like the human brain that are too complex for the necessity of survival. Comparing it to the chimp does not address the point. The chimp lives and is happy.

DAVID: Your response does not explain the human brain. It goes way beyond simple survival.

dhw: Of course it does. It comes under “improvement” – or do you not agree that the human brain is an improvement over the ant brain, the weaverbird brain, the chimp brain in terms of its capabilities?

DAVID: A drive for survival implies a necessity for response to challenges. The human brain is not needed for that. Your improvement then is equal to my complexity drive.

All dealt with above. I prefer “improvement” as I don’t see the point of complexity for the sake of complexity.

DAVID’s comment: Obviously some life forms survive forever with no need to evolve. I repeat my suggestion that there a drive to complexity that obviously is not present in some organisms, which also raises the issue that external stresses and challenges may not be the only driver for evolution of life.

dhw: Not even the sun will survive forever, but we needn’t dwell on that. It is indeed obvious that if any particular form of life survives without changing, it doesn’t need to change! We have said the same thing over and over again about bacteria. You like to talk of a drive to complexity, and I prefer to talk of a drive for survival and/or improvement. The former is a response to stresses and challenges, and the latter is a response to opportunities. As before, I see no purpose in complexity just for the sake of complexity.

DAVID: Your response does not explain the human brain. It goes way beyond simple survival.

dhw: Of course it does. It comes under “improvement” – or do you not agree that the human brain is an improvement over the ant brain, the weaverbird brain, the chimp brain in terms of its capabilities?

A drive for survival implies a necessity for response to challenges. The human brain is not needed for that. Your improvement then is equal to my complexity drive.